Means for the prevention of accidents on railways.



T. C. KERR.

MEANS FOR THE PREVENTION OF ACCIDENTS ON RAILWAYS.

APPLICATION FILED JUNE 12. 1914.

L152,953. Putvnted Sept. T, 1915.

2 SHEETSSHEET I.

THOMAS CURRIE KERR, OF

STEVENSTON, SCOTLAND.

MEANS FOR THE PREVENTION OF ACCIDENTS 0N RAILWAYS.

To all whom it may concern:

Be it known that I, THOMAS CURRm KERR, a subject of the King of GreatBritain, residing at Stevenston, Ayrshire, Scotland, have inventedcertain new and useful Improved Means for the Prevention of Accidents onRailways, of which the following is a specification.

This invention relates to the prevention of collisions on railwaysbetween two or more moving bodies, by which term I mean to cover andinclude, a train, a part of a tram, a car, or a locomotive, and thecharacteristic feature of the invention is that each moving body has asource of electric energy together with means whereby, as the speed ofthe body varies, the effective electric potential will also vary. Ifthere are two such moving bodies on the same track and traveling atdifferent speeds, it follows that the effective electric potentialthereof will be dissimilar and this dissimilarity is taken advantage of,under this invention, to prevent possibility of a collision. The means,employed to this end are simple and efiective and comprise track orother conductors, one, or more than one, electric device on each bodyoperable from the source of electric energy and adapted to control orapply the brakes or to give visible or audible signals and meansconnecting the electric device or devices with said track conductors sothat when the bodies approach within a predetermined distance ofoneanother, a current will flow from the body traveling at the greaterspeed through the electric devices on both bodies and cause theoperation of the signals and or) the application of the brakes. In orderthat the invention may be clearly understood I will now describe thesame with reference, to the accompanying drawings which show, simply byway of example, one mode of carrying it into eli'ect or practice.

On the drawings: Figure 1 is a perspective and diagrammatic View of alength of track having two engines thereon traveling in the samedirection, said track and engines having the invention applied thereto.Fig. 2 is a diagrammatic View of the track and train circuits and Fig. 3shows the insulated conductors a, b, enlarged and in cross section. Fig.a shows a modification.

In carrying the invention into effector practice, according tov thearrangement shown'on the drawings, parallel conductors Specification ofLetters Eatent.

Application filed June 12, 1914. Serial No. 844,662.

Patented Sept. F, 1915,

a: and Z2 are carried by insulatorsc (see particularly Fig. 3) suitablylocated at intervals along the track, these insulators being constructedof insulating material so that the conductors are insulated from thetrack. The conductors are not continuous but are each divided into anumber of sections insulated from one another and the opposite conductorand are so arranged, in staggered relationship, that a gap between anytwo sections of the same conductor shall not, under any circumstances,fallopposite a gap between two sections of the opposite conductor. Thegapsfall some distance apart and the distance between a gap in the oneconductor and the next gap in the other conductor represents thedistance over which protection is obtained. These conductors,preferably, extend the entire length of the track but, if desired, maybe arranged only in suitable lengths, at each signaling area and (or)adjacent to each station or other stopping place. At each signaling areaand (or) station a partial track circuit extends from a section of theconductor 6, by means of a wire 03 to a switch e'and from thence, bywire ,f'to a running rail or other return. The switch a is under thecontrol of the Signalman or other oficial and is, preferably, connectedwith the usual semaphore signaling apparatus and adapted to be closedwhen a danger signal is set and opened when a clear signal is set.

The train portion of the arrangement may be located on any suitable part(or on several parts) of the train but is, in the present instance,located in the engine cab and comprises a collecting bow, trolley, orequivalent 9 connected, by means of a wire z','with one terminal of atime switch it, the other terminal of which is connected with one poleofa i multiple cell battery A. A pole of each cell, or group of-cells,of the battery A, is connected with a stud or contact of a controllingswitch B the arm of which is connected, by means of wire y,

with the engine framing through a suitable electric device, in thiscase, a solenoid C. The switch Bis operable by a rod is connected with acentrifugal governor D which is adapted to be driven from the wheel axles, or other suitable part of the train, which varies in speed inaccordance with the speed of the train, by, anendless I chain Z or otherdriving arrangement.

is suitably The core m of the solenoid G connected, either directly orindirectly, with a valve located in the air or vacuum pipe a connectedwith the brake mechanism. Preferably, in all cases, the core of thesolenoid would have a dash pot in connection with it'to regulate itsaction. In some cases, if so desired, the solenoid may be arranged toactuate a trip lever or the like which, in its turn, would bring intooperation spring or weight mechanism suliiciently powerful to operatethe brake valve.

Instead of the multiple cell battery A. a dynamo may be employed inwhich case the switch Bwould be replaced by a rheostat E (see Fig. l) Insome cases it may be found desirable to use a dynamo and drive itdireotly or indirectly from a wheel axle.

The modes opemmli of the device is as .follows: When a train is at astandstill the governor is at rest and the switch B includes but onecell or group of cells in the partial train circuit, or, if a dynamo isemployed as a source of current, the rheostat E in cludes the maximumresistance in said partial circuit. If desired, the switch or rheostatemay be adapted. to cut all source of power out of the partial traincircuit when .the train is at a standstill, but, as will be hercinafcrapparent, such is not a preferable arrangement. When the train is set339 in niotion the governor D is driven from the Wheel axle, or othersuitable part of the train, by the chain or equivalent Z and, as thespeed of the train accelerates, the weights of the governor move outwardunder cent'ifiugal action and rotates in substantially circular path ofincreasing radius. This XllOVGl'flfilltOf the governor ag'hts causes theswitch B or rheostat E move over number of studs or contacts d. i eludeone or more cells of the batter in partial train circuit or cut out aiber of resistances from and circuit. ten the speed of the train ceasesto accele, the switch or rhecstat arm takes up iefinite position,dependent upon the speed efthe train, and maintains a number of cells ofthe battery A inthe partial train circuit, or maintains a number ofresistances eut of said partial circuit and the greater the speed or thetrain the larger is the number of cells included, orresistancesexcluded, from said. partial circuit, and vice versa;

Now, assume a to have moved over a section of the conductor 72 withwhich a switch 6 is connected. If the switch a is maintained open by thesetting of a clear signal there will be no effect, as no circuit can becompleted from the battery 15. (or dynamo) and the train will be allowedto proceed. If, however, the switch 6 has been closed by'tlie setting;of a danger signal, a circuit is completed as follows (see particularlyFig, 2) from battery A (or dynamo), time switch it, (closed), wire i.bow or equivalent 5 conductor 5, wire 03, switch 8,

'sistances excluded from,

wire f, through running rail and engine frame to solenoid Q, and fromthence through wire j and switch B, or rhccstat E, to battery A, ordynamo. The completion of this circuit energizes the solenoidC andcauses its core m to open the valve in the air or vacuum brake pipe aand apply the brakes, also, if desired, at the same time, sound an alarReferring now more particularly to Fig. 1, if the engines F and beingeach over the same section of the conductor Z, are

traveling at the same speed each will have the same number of cellsincluded in, or reits partial train circuit and, consequently, owing toequal voltage being in each source of supplyyno current will flow fromeither engine and, provided their signals are clear, both will beallowed to proceed. If, however, the engine increases in speed and tendsto overtake the engine G, the governor D will cause the switch B of theformer engine to include more cells in, or exclude more resistancesfrom, the partial train circuit thereof and thus cause the electricpressure in one battery to exceed that of the other and a current willflow tollow battery A, or dynamo, through time switch.

(closed) wire 2' and collecting how 9 of engine F, along conductor 5, toengine G through how g, wire 2', time .Witch it (closed), battery A, ordynamo, switch E, or rheostat E, wire j, solenoid C, and frame sa atterengine to the running rails by which it returns to engine and throsolenoid C, wire j, and switch B, or rhea; E, to battery A, or dynamo,oi same. Th s current energizes the solenoids J oi both engines andcauses the brakes to be applied on both trains bringing both to astandstill. and preventing possibility of a col. on.

it will, of course, be obvious that a cur rent would flow in the samemanner, and have the same effect, if the engine G were stationary.

The battery or dynamo employed in connection with the presentarrangement may, if desired, be the same as that used to effect thelighting of the train, or portion of the train, or may, of course, beentirely dis tinct from same.

The function of the time switch it, which. is controlled by clockwork,or dash pot, or equivalent, solenoids to be broken, for a predeterminedtime only, to allow oi movement for shunting, movement of train out offan area, or such like, even if the train should be over the same sectionof cond ctor as another train on the seine track. his switch may beopened manually but is closed auto1natically at expiration of a shortand. prcdetermined interval.

A number of simple czmnecting cables of is to enable the circuit to thesuitable length or lengths, the ends of each being provided with clipsor hand clamps adapted to be detachably secured to the conductors andrunning rails are, preferably, provided on each train. In case it shouldbecome necessary to stop the approach of trains in either, or bothdirections owing to a train, or part of a train becoming derailed, orfor other reasons, these connecting cables may be utilized as temporarylocal switches to block the approach of trains by connecting same acrossone or more of the conductors and its or their juxtaposed running rail,or other return.

,In all cases, I prefer to arrange an installation on the engine andanothersimilar or modified installation in the guards van in case oneinstallation should fail to operate from any cause.

If desired, in some cases, I may arrange for the electrical conductorsto be carried on posts at the side of the track, and the bow (ortrolley) would be suitably arranged to w rk in conjunction therewith. D

' n all cases where I refer to tram or trains it is to'be understood Iintend to include portions of trains, whenever it may be deemednecessary or advisable .to provide such portions with an electricinstallation.

Having now fully described my invention,

what I claim and desire to secure by Letters.

" Patent is a partial circuit,

1'. The combination, on a moving body, of a multi-cell battery and meanswhereby as the speed of the body varies a varying number of cells ofsaid battery will be included in said partial circuit.

2. The combination, on a train or part thereof, of a partial circuit, amulti-cell battery, a governor operable from a movable part of the trainand a switch, operable 'from said governor, adapted to include a numberof cells in said partial circuit.

3. Means for preventing collis ons on railways between two moving bOdlGScomprising electric conductors for the track, a partial circuit on eachbody, means connecting said partial circuits with the track conductors,an electric device in each partial circuit, a 'multi-cell battery oneach body and means,- on each body, for including a num- 1 her,dependent upon the speed of the body,

of cells of circuit.

4, Means for preventing collisions on railways between two trainscomprising electric conductors for the track, a partial circuit thebattery in thatbodys partial on each train, means connecting saidpartial circuits with the track conductors, ancelectric device in eachpartial circuit, a source of electricity connected with each partialcircuit, a governor on each train operable from a movable part of thetrain and means, on each train, operable from said governor, for varyingthe potential of the electric energy transmitted from its source ofelectricity to its partial circuit.

5. Means for preventing collisions on railways between two moving bodiescomprising electric conductors for the traclr, a partial circuit on eachbody, means connecting said partial circuits with the track conductors,an electric device in each partial circuit, a source of electricityconnected with each partial circuit, a governor on each body operablefrom a movable part thereof, and switch means, on each body, operablefrom said governor, for varying the potential of the electric energytransmitted from its source of electricity to its partial circuit.

6. Means-for preventing collisions on railways between two movmg bodiescomprising a partial circuit on each body, an electric device in eachpartial circuit, a source of electricity connected with each partialcircuit, a governor on each body operable from a movable part thereof,means on each body,

operable from said governor, for varying the potential of the electricenergy trans-

